With the increasing use of haptic effects to enhance a user's experience in a plethora of digital content applications, it is desirable to efficiently store and/or transmit haptic data together with other digital content (e.g., multimedia data) over a network. A haptic data stream is typically represented in raw pulse code modulation (“PCM”) data format. To stream haptic data sampled in 8 bits at 8000 samples per second over a network (wired or wireless), 64 kbits (8 KB) per second, or an extra 8 KBps should be transferred on the bandwidth. However, there may be periods of silence in the stream, i.e. periods during which no haptic data is streamed, which may waste time and bandwidth by streaming zeroes or unnecessary data over the network, and is not ideal for both the content distributor and the end user. The storing of haptic data streams faces the same challenge.
With respect to digital content streaming, adaptive bit rate streaming is a common practice for varying the quality of audio/video signals when streaming or transmitting large amounts of data over a digital network. This is done so that the smooth streaming or playback of audio and video signals is still feasible by adapting to varying network speeds and/or congestion. For example, if a video is streaming at very high quality, and then the network over which it is streaming experiences heavy network congestion, or the download speed suddenly becomes slower, the streaming server can still transmit data, but will transmit lower quality data to conserve network bandwidth. Once the congestion has been mitigated and the network speed has increased, the data sent will be higher quality as network bandwidth is more freely available. This may be done by encoding data at multiple bit rates so that the amount of data to be transmitted is much less.
Haptic signals may be interpreted as audio signals if the signal is simply a waveform. However, simply treating haptic signals like audio signals and transcoding the haptic signal at multiple bit rates may not offer much room to adapt the quality for various network speeds. A high quality haptic signal may be considered to have a sample rate of 8 kHz, which is considered to be a very low sample rate for an audio signal and would be a low quality signal. By simply degrading the quality of the haptic signal, a completely different user experience may be introduced, and degrading the quality by just arbitrarily removing bits of the same stream may result in unintended texturing and take away from the clarity of the signal.